INHIBITING EFFECT OF NITRITES ON THE CORROSION OF REBARS EMBEDDED IN CARBONATED CONCRETE . ADMIXTURES FOR CONCRETE: IMPROVEMENT OF PROPERTIES. PROCEEDINGS OF THE INTERNATIONAL SYMPOSIUM HELD BY RILEM (THE INTERNATIONAL UNION OF TESTING AND RESEARCH LABORATORIES FOR MATERIALS AND STRUCTURES), BARCELONA, MAY 14-17, 1990

Concrete carbonation induces a pH drop of the pore solution down to values around the neutrality. When the carbonation front reaches the rebar, the steel is depassivated and its corrosion starts at a rate which depends on the humidity inside the concrete pores. In order to prevent or avoid this corrosion, several methods have been developed which, in general, need to be foreseen during the design or the construction. In the present paper, results on the inhibiting effect of nitrites, added as admixtures during the mix, on the rebar corrosion in carbonated concrete, are presented. Nitrites have been tested in concrete as inhibitors of the chloride attack, but their effect against carbonation is poorly known. The tests have been carried out in mortar. The results show that nitrites passivate the steel in carbonated media, regardless the solution pH value or the cement type. When the inhibiting action is not complete, at least the reduction of the corroding area is very high. The inhibiting effect was not detected when chlorides were added to the mixing before carbonation. (Author/TRRL)

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/0412374102
• Corporate Authors:

  Chapman and Hall Limited

  11 New Fetter Lane
  London,   England 
• Authors:
  • Alonso, C
  • ACHA, M
  • Andrade, C
• Publication Date: 1990

Language

• English

Media Info

• Features: References;
• Pagination: p. 219-228
• Serial:
  • Publication of: Chapman and Hall
  • Publisher: Chapman and Hall Limited

Subject/Index Terms

• TRT Terms: Admixtures; Carbon; Concrete; Conferences; Corrosion protection; Material reinforcement; Nitrites; Physical properties; Reinforcing bars
• Uncontrolled Terms: Concrete properties; Rebars
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00612203
• Record Type: Publication
• Source Agency: Transport and Road Research Laboratory (TRRL)
• ISBN: 0-412-37410-2
• Files: ITRD, TRIS
• Created Date: Aug 31 1991 12:00AM